1 1 8 Permanence and Evolution. 



sive complexity of complexity proportioned 

 to their elevation as organisms, and whose 

 systematic affinity is dependent on the resem- 

 blance between their elements, and that the 

 excessive rarity of their appearance de nova 

 on this planet arises from the complexity 

 and consequent rarity of the collocations of 

 matter necessary to produce them ; this hypo- 

 thesis, though totally without positive evidence 

 to support it and I certainly do not mean to 

 propose or defend it, is in itself quite as clear and 

 definite, and (what is called) explains the facts 

 about as well as the hypothesis of evolution. 



To me it seems that the reason why the hypo- 

 thesis of evolution appears to many so much 

 more easily conceivable than any other mode of 

 origination, arises mainly from utterly vague and 

 inadequate notions as to the strictness of in- 

 heritance, which vagueness is itself the result of 

 forming our notions mainly from highly mixed 

 races, such as civilised man and domestic animals. 



